| A study was conducted at the agricultural experiment farm of Upjohn Pharmaceutical Co., Kalamazoo, Michigan to evaluate agricultural land application of mycelia filter cake derived from lincomycin production. Lincomycin mycelia filter cake was applied to a Kalamazoo sandy loam soil (fine-loamy, mixed, mesic Typic Hapludalf) in the spring of 1980 and 1981 at rates of 0, 7.5, 16.0 and 30.5 dry metric tons/ha. The lincomycin filter cake proved toxic to corn in 1980 so winter wheat was planted to half of the field to check residual toxic effects. A change in the lincomycin production process and a period of 34 days between application of the filter cake and planting of corn resulted in no toxic effects to corn in 1981. The winter wheat showed no residual toxicity from the 1980 application of lincomycin and samples of wheat grain, corn grain and corn leaf tissue, all from the 1981 crops, showed no uptake of lincomycin. In 1981 the yield of wheat was 15.8, 26.5, 31.2, and 41.7 hl/ha for 0, 7.5, 16.0, and 30.5 dry metric tons/ha of filter cake, respectively. The corn yields were 49, 67, 84, and 90 hl/ha for the same rates respectively. The yields for the high rates compared well with commercially fertilized fields of corn and wheat on similar soil types.;Data from suction cup lysimeters and from soil samples showed that NO(,3) and soluble-salts were moving downward through the soil profile and that the conversion from NH(,4) to NO(,3) was slowed down by the lincomycin wastes.;The results from this experiment indicate that application of lincomycin mycelia filter cake on agricultural land at the rate of 16.0 dry metric tons/ha is environmentally safe with regard to NO(,3) pollution of groundwater. When added to the soil, this antibiotic waste material is degraded by soil organisms into useful nutrients. These nutrients are readily utilized by crops and the antibiotic is not translocated into the plant. |
